复杂开口房间火灾中性层位置的计算

Calculation of Neutral Surface Position of Room in Fire with Multi-opening

本文建立了复杂开口房间的数学模型,并运用等效窗口面积法对复杂开口条件(门窗同时开启)下房间中性层关系进行了数学推导,对单一开口和复杂开口房间发生火灾时房间门和窗同时开启状态下中性层位置进行求解和比较分析,同时还对不同温度下房间孔洞的烟气、空气质量流量进行了计算和比较;对在室内温度逐渐升高的情况下房间中性层高度的变化进行了研究和分析。从而得出多开口不同开口高度条件下中性层位置的求解方法,温度与中性层高度、烟气质量流量、空气质量流量的关系,以及空气改善系数对烟气、空气质量流量和中性层高度的影响。

In the paper, the mathematical model of multi-opening room in fire is presented. The neutral surface relation of multi-opening (with door and window both opened) room is derived by using Equality Window Dimension method. Finally, the neutral surface position of both single opening room and multi-opening room are computed and analysed when fire takes place with both door and window open.The mass flow of smoke and air under different room temperature is calcuted; and the variation of the neutral surface height is studied along with the rising of room temperature. The method for computing neutral surface position of room with multi-opening & different opening height is obtained along with the relationship between neutral surface, mass flow of smoke & air and room temperatures .The affection of air ameliorating factor on mass flow of smoke & air and neutral surface height is discussed.